To make a part out of such a composite material, the procedure is generally to make a fiber preform whose shape is similar to that of the part to be made, and then to densify the preform by infiltrating with the material that constitutes the matrix within the pores of the preform. Densification may be performed using a liquid (impregnation-pyrolysis cycle(s)) or by using a gas (chemical vapor infiltration cycle(s)).
The present invention seeks more particularly to fabricate a composite material reinforced by ceramic fibers, in particular fibers derived from organo-metallic precursors, e.g. fibers made essentially of silicon carbide or of silicon nitride and derived from organo-silicon precursors.
Compared with fibers obtained by chemical vapor deposition of a ceramic coating on a metal or a carbon core, fibers obtained by pyrolysis (ceramization) of an organo-metallic precursor are generally more suitable for being subjected to textile operations, in particular weaving, and they are cheaper. However, their mechanical properties are still limited.
An object of the present invention is to remedy these drawbacks by proposing a method enabling the mechanical behavior of these fibers to be improved, and consequently enabling the mechanical behavior of composite materials in which such fibers are used as reinforcement to be improved.